patch 8.2.1839: Vim9: memory leaks reported in assign test

Problem:    Vim9: memory leaks reported in assign test.
Solution:   Move the failing job_start() call to separate test files, it
            causes false leak reports.

src/version.c

@@ -750,6 +750,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1839,
 /**/
     1838,
 /**/